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某网站包含两个表,Customers 表和 Orders 表。编写一个 SQL 查询,找出所有从不订购任何东西的客户。
Customers
+----+-------+| Id | Name | +----+-------+ | 1 | Joe || 2 | Henry | | 3 | Sam || 4 | Max | +----+-------+
Orders
+----+------------+| Id | CustomerId | +----+------------+ | 1 | 3 || 2 | 1 | +----+------------+
例如给定上述表格,你的查询应返回:
+-----------+| Customers |+-----------+| Henry || Max |+-----------+
Solution
SELECT c. NAME AS customers FROM customers c WHERE c.id NOT IN ( SELECT a.id FROM customers a, orders b WHERE a.id = b.customerId );
作者:lconcise
链接:https://www.jianshu.com/p/80b6b7517a8d
来自 “ ITPUB博客 ” ,链接:https://blog.itpub.net/166/viewspace-2816245/ ,如需转载,请注明出处,否则将追究法律责任。